Photovoltaic devices are known in the art (e.g., see U.S. Pat. Nos. 6,784,361, 6,288,325, 6,613,603, and 6,123,824, the disclosures of which are hereby incorporated herein by reference). Some conventional mainstream photovoltaic modules use a large number of crystalline silicon (c-Si) wafers. The inclusion of the large number of c-Si wafers tends to dominate the cost of the overall photovoltaic module. Indeed, about 60% of the costs involved in the production of conventional photovoltaic modules is related to the c-Si solar cells. To address this issue, concentrated photovoltaic (CPV) systems have been proposed, in which the sunlight is to be focused with concentration ratios of 100× to 1000×. Calculations suggest that a concentration ratio of approximately 10× should enable a photovoltaic system to be produced that uses at least 90% less silicon material.
Unfortunately, however, current concentrated photovoltaic systems use expensive high efficiency multi-junction solar cells, expensive dual-axis tracking systems, and/or relatively expensive concentrating optics. Therefore, these systems have difficulty competing with other photovoltaic solutions on a cost per watt basis.
Thus, it will be appreciated there is a need in the art for a simple low-cost CPV systems, together with low cost solar cells and low-cost concentrating optics, and/or methods of making the same.
One aspect of certain example embodiments relates to a patterned glass cylindrical lens array, and/or methods of making the same.
Another aspect of certain example embodiments relates to using such a cylindrical lens array to focus light on substantially elongate or strip solar cells.
Another aspect of certain example embodiments relates to lateral displacement tracking systems, and/or methods of making and/or using the same.
Still another aspect of certain example embodiments relates to a static or semi-static system, where the assembly is either fixed or adjustable to two or more predefined locations, e.g., to take into account seasonal and/or other variations in the solar elevation angle.
Still another aspect of certain example embodiments relates to the design of a system, where the assembly is either fixed or adjustable to two or more predefined locations, e.g., to tune the Solar Heat Gain Coefficient or SHGC (for instance, to balance heating and/or cooling, lighting, and/or other issues, potentially on a seasonal basis).
Further aspects of certain example embodiments relate to building-integrated photovoltaic systems, which may include insulating glass units comprising cylindrical lens arrays and strip solar cells. In certain examples, the photovoltaic system may be integrated into a building as an insulated glass skylight.
In certain example embodiments, a building-integrated photovoltaic (BIPV) system (e.g., photovoltaic skylight) may be provided on the roof of a building and/or other suitable structure. In certain example instances, the photovoltaic skylight may be installed on a roof at latitude tilts and may transmit diffuse daylight into the interior of the building, while converting direct sunlight into electricity at a relatively high efficiency.
In certain example embodiments of this invention, a skylight is provided. A plurality of solar cells is supported by a substrate. A lens array comprises a plurality of lenses oriented along a common cylindrical axis that is substantially parallel to the ground. Each said lens is configured to concentrate light on the solar cells, and the lens array is spaced apart from the substrate supporting the solar cells such that a gap is defined between the lens array and the substrate and such that the lens array and the solar cells remain in fixed position relative to one another.
In certain example embodiments of this invention, a skylight is provided. A plurality of solar cells is supported by a substrate. A lens array comprising a plurality of lenses is oriented along a common axis. Each said lens is configured to concentrate light on the solar cells, and the lens array is spaced apart from the substrate supporting the solar cells such that a gap is defined between the lens array and the substrate. The lens array and the solar cells are movable relative to one another as between at least first and second predefined positions.
Similar windows, BIPV devices, and/or other products also are contemplated herein. Such products may be used, for instance, in commercial and/or residential settings.
In certain example embodiments of this invention, a method of making a building integrated photovoltaic device is provided. The method may include, for example, providing a substrate supporting a plurality of generally elongate solar cells; providing a lens array comprising a plurality of lenses oriented along a common cylindrical axis; and connecting the substrate and the lens array in spaced apart but fixed relation to one another so that the cylindrical axis is substantially parallel to the ground, and so that each said lens is configured to concentrate light on the solar cells.
In certain example embodiments of this invention, a method of making a building integrated photovoltaic device is provided. The method may include, for example, providing a substrate supporting a plurality of generally elongate solar cells; providing a lens array comprising a plurality of lenses oriented along a common axis; and connecting the substrate and the lens array in spaced apart relation to one another, so that each said lens is configured to concentrate light on the solar cells. The lens array and/or the solar cells are movable relative to one another as between at least first and second predefined positions.
Corresponding methods of making skylights, BIPV devices, windows, and/or the like also are contemplated herein. For instance, a building integrated photovoltaic device made in accordance with such methods may be built into a window, skylight, etc.
In certain example embodiments of this invention, a skylight is provided. A lenticular array is provided along a common axis. A substrate supports a plurality of generally elongate solar cell strips. The lenticular array and the substrate are oriented relative to one another such that the skylight has different solar heat gain coefficients (SHGCs) during at least first and second times of the year, respectively.
The same or similar structure may be used in connection with a BIPV product, window, and/or the like, e.g., in commercial and/or residential applications. For example, in certain example embodiments of this invention, a building integrated photovoltaic (BIPV) product is provided. An array of lenses is provided along a common axis. A substrate supports a plurality of generally elongate solar cell strips. The array of lenses and the substrate are oriented relative to one another such that the skylight has different solar heat gain coefficients (SHGCs) during at least first and second times of the year, respectively. The different SHGCs are at least partially controlled by designing the skylight such that different amounts of direct sunlight impinge upon the solar cell strips at corresponding times of the year.
In a similar vein, methods of making the same or similar structure may be provided, e.g., in connection with a skylight, BIPV product, window, and/or the like, e.g., in commercial and/or residential applications. For instance, in certain example embodiments of this invention, a method of making a window is provided. The method may comprise building a building integrated photovoltaic (BIPV) product made in accordance with the methods described herein into a window.
In certain example embodiments, the BIPV system may include a photovoltaic skylight. In some cases, the photovoltaic skylight may comprise an insulated glass unit (IGU).
The features, aspects, advantages, and example embodiments described herein may be combined to realize yet further embodiments.